From b057878b2aadc7e06280e7e702a36e7adb1bcdf7 Mon Sep 17 00:00:00 2001 From: Juergen Gross Date: Thu, 22 Sep 2016 10:45:41 +0200 Subject: [PATCH] xen/pciback: support driver_override Support the driver_override scheme introduced with commit 782a985d7af2 ("PCI: Introduce new device binding path using pci_dev.driver_override") As pcistub_probe() is called for all devices (it has to check for a match based on the slot address rather than device type) it has to check for driver_override set to "pciback" itself. Up to now for assigning a pci device to pciback you need something like: echo 0000:07:10.0 > /sys/bus/pci/devices/0000\:07\:10.0/driver/unbind echo 0000:07:10.0 > /sys/bus/pci/drivers/pciback/new_slot echo 0000:07:10.0 > /sys/bus/pci/drivers_probe while with the patch you can use the same mechanism as for similar drivers like pci-stub and vfio-pci: echo pciback > /sys/bus/pci/devices/0000\:07\:10.0/driver_override echo 0000:07:10.0 > /sys/bus/pci/devices/0000\:07\:10.0/driver/unbind echo 0000:07:10.0 > /sys/bus/pci/drivers_probe So e.g. libvirt doesn't need special handling for pciback. Signed-off-by: Juergen Gross Signed-off-by: David Vrabel --- drivers/xen/xen-pciback/pci_stub.c | 36 ++++++++++++++++++++++++------ 1 file changed, 29 insertions(+), 7 deletions(-) diff --git a/drivers/xen/xen-pciback/pci_stub.c b/drivers/xen/xen-pciback/pci_stub.c index 01793332f7e6..6331a95691a4 100644 --- a/drivers/xen/xen-pciback/pci_stub.c +++ b/drivers/xen/xen-pciback/pci_stub.c @@ -25,6 +25,8 @@ #include "conf_space.h" #include "conf_space_quirks.h" +#define PCISTUB_DRIVER_NAME "pciback" + static char *pci_devs_to_hide; wait_queue_head_t xen_pcibk_aer_wait_queue; /*Add sem for sync AER handling and xen_pcibk remove/reconfigue ops, @@ -508,15 +510,18 @@ static void pcistub_device_id_add_list(struct pcistub_device_id *new, kfree(new); } -static int pcistub_seize(struct pci_dev *dev) +static int pcistub_seize(struct pci_dev *dev, + struct pcistub_device_id *pci_dev_id) { struct pcistub_device *psdev; unsigned long flags; int err = 0; psdev = pcistub_device_alloc(dev); - if (!psdev) + if (!psdev) { + kfree(pci_dev_id); return -ENOMEM; + } spin_lock_irqsave(&pcistub_devices_lock, flags); @@ -537,8 +542,12 @@ static int pcistub_seize(struct pci_dev *dev) spin_unlock_irqrestore(&pcistub_devices_lock, flags); - if (err) + if (err) { + kfree(pci_dev_id); pcistub_device_put(psdev); + } else if (pci_dev_id) + pcistub_device_id_add_list(pci_dev_id, pci_domain_nr(dev->bus), + dev->bus->number, dev->devfn); return err; } @@ -547,11 +556,16 @@ static int pcistub_seize(struct pci_dev *dev) * other functions that take the sysfs lock. */ static int pcistub_probe(struct pci_dev *dev, const struct pci_device_id *id) { - int err = 0; + int err = 0, match; + struct pcistub_device_id *pci_dev_id = NULL; dev_dbg(&dev->dev, "probing...\n"); - if (pcistub_match(dev)) { + match = pcistub_match(dev); + + if ((dev->driver_override && + !strcmp(dev->driver_override, PCISTUB_DRIVER_NAME)) || + match) { if (dev->hdr_type != PCI_HEADER_TYPE_NORMAL && dev->hdr_type != PCI_HEADER_TYPE_BRIDGE) { @@ -562,8 +576,16 @@ static int pcistub_probe(struct pci_dev *dev, const struct pci_device_id *id) goto out; } + if (!match) { + pci_dev_id = kmalloc(sizeof(*pci_dev_id), GFP_ATOMIC); + if (!pci_dev_id) { + err = -ENOMEM; + goto out; + } + } + dev_info(&dev->dev, "seizing device\n"); - err = pcistub_seize(dev); + err = pcistub_seize(dev, pci_dev_id); } else /* Didn't find the device */ err = -ENODEV; @@ -975,7 +997,7 @@ static const struct pci_error_handlers xen_pcibk_error_handler = { static struct pci_driver xen_pcibk_pci_driver = { /* The name should be xen_pciback, but until the tools are updated * we will keep it as pciback. */ - .name = "pciback", + .name = PCISTUB_DRIVER_NAME, .id_table = pcistub_ids, .probe = pcistub_probe, .remove = pcistub_remove, -- 2.20.1